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Programming notes:

Normally, a filter or command handler may be destroyed when the tab is no longer required and recreated when it is displayed (the random creation/destruction process is controlled by the system, not the Framework). If a filter or a command handler is heavily used, this process can be costly and can be avoided by setting Stay Active to YES.

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If you use uInitialize and uTerminate with a non-stay active filter or command handler they still work, but they may be invoked frequently as the filter or command handler is being created and destroyed, and they do not run every time the object is hidden and displayed.

This property is in the Commands Allowed tab and the Filter Snap-in Settings tab.